To achieve miniaturization and high functionality of a semiconductor device, a semiconductor device having a system in package (SiP) structure in which a plurality of semiconductor chips are laminated in one package and are sealed therein has been developed. In the semiconductor device having the SiP structure, high-speed transmission and reception of electrical signals between semiconductor chips are required. In this case, a micro-bump is used for electrical connection between the semiconductor chips. For example, the micro-bump has a diameter of approximately 5 μm to 50 μm, and is formed on a surface of each of the semiconductor chips and is formed of individual solder bumps having a pitch of approximately 10 μm to 100 μm.
In the semiconductor device, it is preferable to suppress bonding failures at or in the micro-bump.